Subsurface well bore valve apparatus



Aug. 26, 1958 M. B. CONRAD suBsuRFAcE WELL BoRE VALVE iAPmRATus BYlinfo/@A454452 Aug. 26, 1958 M. B. CONRAD 2,849,207

sUBsURFAcE WELL Bom: VALVE APPARATUS Filed Jan. so. 1956 s sheets-sheet2 N V EN TOR. Maer//v CoA/Q40 BY I . M )v/Md Aug. 26, 1958 M. B. coNRAD2,849,207

sUBsURFAcE WELL BoRE VALVE APPARATUS n s sheets-sheet s Filed Jan. 30.1956 IN VEN TOR.

Mair/N E. CoA/,ewa BY United States Patent O SUBSURFACE WELL Bonn VALVEAPPARATUS Martin B. Conrad, Downey, Calif., assignor to Baker Oil Tools,Inc., Los Angeles, Calif., a corporation of California ApplicationJanuary 30, 1956, Serial No. 562,235 1s Claims. (01.251-149) The presentinvention' relates to valve apparatus, and more particularly to valveapparatus adapted to be disposed in well bores to control the iiow offluids therein.

Valve apparatus may be incorporated in a tubular string disposed in awell bore to control the How of uid in the tubular string. For manyapplications, it is desirable for the passage or bore through the valveapparatus to be of relatively large size and free from restrictions, toavoid the retarding of iluid flow through the apparatus when open, andto minimize erosive wear on its parts. In fact, it is preferred to havethe passage through the valve apparatus at least as large in diameter asthe bore through the tubular string extending to the top of the hole,Despite the presence of a large diameter passage through the valveapparatus, certain of its portions, such as a valve head movable intoand out of engagement with a companion valve seat, may be subject toerosive wear by fluid passing thereby.V

Di'iculties are encountered in attempting to provide a full openingthrough a valve apparatus of the character described, and in protectingits valve head against erosive wear. Part of the difliculty involves thelimited maximum outside diameter of the valve apparatus that can beused, in view of the restrictions presented by well holes of relativelysmall size, or of small diameter casing, or similar pipe, therein.

An object of the present invention is to provide a valve apparatusadapted to be incorporated in a tubular string disposed in a well boreand extending to the top of the latter, in which the valve apparatus canbe placed selectively in an open or closed position, the passage throughthe apparatus being of large diameter as compared to its outsidediameter, the valve head being substantially fully protected from theuent material liowing through the passage when open. In a more limitedsense, the open passage through the valve apparatus can be at least aslarge in diameter as the inside diameter of the tubular string, thepassage being unrestricted throughout its length.

Another object of the invention is to provide a valve apparatus adaptedto be incorporated in a tubular string to be located in a well bore, thevalve apparatus embodying a valve head movable into and out ofengagement with a companion seat, in which the valve head can bepositively cammed to an open position in response to rotation of thetubular string, and held positively in such open position protected fromthe uent material owing through the lopen valve apparatus.

A further object of the invention is to provide a valve apparatus forincorporation in a tubular string to be disposed in a well bore, thevalve apparatus being readily shifted between open and closed positionsin response to longitudinal movement of the tubular string, and in whichthe valve apparatus can be positively shifted to an open position inresponse to rotation of the tubular string, in the event fluid pressuretends to maintain the valve apparatus in closed condition.

An additional object of the invention is to provide a ice ' valveapparatus for incorporation in a tubular string to be disposed in a wellbore, which has a full, unobstructed passage therethrough when in openposition, to insure unimpeded iiow of fluid through the passage, thevalve apparatus parts being strong and sturdy, despite the fact that thepassage diameter is comparatively large compared to the over-alldiameter of the valve apparatus, and the space for locating'certainvalve parts in the valve apparatus is comparatively small.

This invention possesses many other advantages, and has other objectswhich may bemade more clearly apparent from a consideration of a form inwhich it may be embodied. This form is shown in the drawingsaccompanying and forming part of the present specification. It will nowbe described in detail, for the purposeof illustrating the generalprinciples of the invention; but

it is to be understood that such detailed description is not to be takenin a limiting sense, since the scope of the invention is best dened bythe appended claims.

Referring to the drawings:

Figure 1 is a longitudinal section showing an embodiment of theinvention with the valve in fully open position;

Fig. 2 is a view si'milar to Fig. l disclosing the valve in closedposition;

Fig. 3 is a view similar to Fig. 1 with the valve parts in an openposition preparatory to being shifted to the position disclosed in Fig.1;

Fig. 4 is a cross-section taken along the line 4 4` on Fig. 3;

Fig. 5 is a cross-section taken along the line 5-5 in Fig. 3;

Fig. 6 is an enlarged cross-section taken along the line l 6-6 on Fig.2;

Fig. 7 is an enlarged cross-section taken along the line 7-7 on Fig. l;

Fig 8 is a fragmentary section taken generally alongA the line V8 8 onFig. 2. v

The apparatus A disclosed in the drawings is adapted to be incorporatedin a tubular string B, such as a string of drill pipe or tubing,extending to the top of the well" bore. The apparatus may be attached tothe lower end of such a tubular string, the lower portion of theapparatus, in turn, being adapted to be secured to a lower tool C, whichmay be a well-packer that is to be anchored in packed-o conditionagainst a well casing (not shown).

The valve apparatus includes an upper tubular mandrel 10, movablelongitudinally with a housing structure,

adjacent the lower end 12 of the upper mandrel. When in this. position,the two mandrels 10, 13 form, in elfect, a continuous passage 15therethrough that has a relatively large diameter. The diameter of thepassage may be at least equal to the internal diameter of the tubularstring B itself.

The upper mandrel 10 is attached to the housing 11 l and can rotate withrespect thereto to a limited extent. Thus, the mandrel 10 has anexternal flange 16 adapted to' engage an inner ange 17 on an upperhousing member 18, the upper end of the mandrel flange 16 beingengageable with the lower end of a nut 19 threaded into the upper end ofthe upper housing member 18, thehead 20 of the nut engaging the end ofthe latter. The lower end of the nut 19 and the inner flange 17 of thehousing form an internal groove 21 rotatably receiving the mani drelflange 16. The mandrel 10 can be turned with respect to the housing 18to a limited extent. Thus, the ange portion 16 is cut away or isprovided with a recess 22 to receive a transverse pin 23 welded to thehousing 18, the pin being engageable with the opposite ends 24, 25 ofthe recess, to locate the valve parts in particular positions, in themanner described hereinbelow.

The upper housing member .18 extends downwardly, its lower end beingthreadedly secured to a lower housing member 26 having an inwardlydirected llange 27 slidably engaging the periphery of the lower mandrel13 above a flange 28 on the latter. This ilange 28 is movable relativelydownward with the lower mandrel 13, such downward movement being limitedby engagement with an inwardly directed flange 29 o n the lower nut 30threaded onto the lower end of the lower housing member 26; The housing11 and lower mandrel 13 can move longitudinally with respect to eachother, as limited by engagement of the mandrel ange 28 with the lowernut flange 29 and the inwardly directed iinage 27 of the lower housingmember. However, the parts are prevented from rotating with respect toeach other, by virtue of a longitudinally extended key 31 welded, orotherwise suitably secured, to the inner wall of the lower housingmember 26 and relatively slidable in a keyway 32 provided in the lowermandrel ilange 28 (Fig. 5).

The inside diameter of the vupper tubular member 18 between its upperinwardly directed flange 17 and the upper end of the lower housingmember 26 is substantially greater than the external diameter of theupper and lower mandrels 10, 13, to provide an annular space 33therebetween in which a valve head 34 can be confined. This valve headis of a flapper valve type and is adapted to move upwardly intoengagement with the companion seat 12 provided by the lower end of theupper mandrel 10, in order to close the passage 15 through the uppermandrel. This valve head is also engageable with the upper end 14 of thelower mandrel 13, to close the passage through the latter member, all asdescribed hereinbelow.

The valve head 34 is disposed in a pendant position within the annularspace 33, when the valve is in fully open position, the upper end of thevalve head having a transversely extending arrn or pivot 35 receivedwithin thebore 36 provided in the lower projection 37 of a valvesupporting ring 38 that bears against the inner ange 17 of the housing11. The ring 38 is held in its upper position against the llange 17 by arelatively thin spacer sleeve 39engaging the inner wall of the upperhousing portion 18, the lower end of the sleeve bearing against theupper end of the lower housing member 26, and its upper end bearingagainst the ring 38. The ring, itself, is prevented from rotating by apin 40 extending into the ring and the inner housing ilange 17. Aleaf-spring arm 41 is struck inwardly from the sleeve 39, and bearsagainst the outer surface of the valve head 34, tending to shift itinwardly of the mandrels 10, 13.

Leakage of fluid between the exterior of the upper mandrel 10 and theupper housing member 18 is prevented by a suitable seal ring 42, such asa rubber or rubber-like ring, disposed in an internal groove 43 in thehousing ilange 17 and bearing against the periphery of the upper mandrel10. Similarly, leakage of fluid between the lower mandrel 13 and thelower housing member 26 is prevented by a suitable seal ring 44, such asa rubber or rubber-like O ring, disposed in an internal groove 45 in thehousing flange 27 and slidably sealing against the periphery of thelower mandrel 13 above its llange 28. Leakage of fluid through thethreaded connection between the housing members 18, 26 may be preventedby a suitable side seal ring 46 provided in a groove 47 in the lowerhousing member 26 and engaging the inner wall of the upper housingmember 18,

It is to be noted that the valve seat 12 at the lower end of the uppermandrel is inclined to the axis of the apparatus by a substantialextent. The valve head 34 may be retained completely within the annularspaces 33 between the mandrels 10, 13 and the housing 11, and

when permitted to do so it can be shifted upwardly into engagement withthe inclined valve seat 12, beingpositively held thereagainst by thebearing of the companion inclined upper end 14 of the lower mandrel 13against the back surface 48 of the valve head. As disclosed in Fig. l,the upper mandrel 10 and housing 11 have been moved in a downwarddirection relative to the lower mandrel 13, in which position the lowermandrel 13 is disposed completely across the valve head 34 to conne itentirely within the annular housing space 33. When the valve parts arein the positions described, the inclined ends 12, 14 of the upper andlower mandrels 10, 13 are closely adjacent to one another, and Iluidscan then pass freely through the full opening 15 in the mandrels in bothlongitudinal directions.

When the valve apparatus is to be closed, it is only necessary toelevate the tubular string B, which will lift the upper mandrel 10 andhousing 11 with respect to the lower mandrel 13, the housing beingelevated to the extent determined by engagement of the lower nut ilange29 with the lower mandrel ange 28, such as disclosed in Fig. 3. When theparts are in this position, the upper end 14 of the lower mandrel isdisposed below the depending valve head 34, allowing the leaf spring 41to shift the valve head inwardly, in which it will be disposed in aninclined state across the upper end of the lower mandrel member 13. Atthis time the upper mandrel member 10 still occupies the rotationalposition with respect to the lower member 13 disclosed in Fig. l. Withthe valve head 34 extending in an inclined position partly across theupper end 14 of the lower mandrel, the tubular B string, upper mandrel10, and housing 11 need merely be lowered once again with respect to thelower mandrel 13, such lowering movement carrying the valve head 34downwardly into engagement with the upper end 14 of the lower mandrel,causing the latter to swing the valve head upwardly about its pivot 35into engagement with the valve seat 12 at the lower end of the uppermandrel 19. Downward movement of the upper mandrel 19 and housing 11with respect to the lower housing 13 is limited by such engagement ofthe valve head 34 against the valve seat 12 and by the engagement of theback side 48 of the valve head against the upper end 14 of the lowermandrel 13. The parts then occupy the position disclosed in Fig. 2, inwhich the valve is in closed position, the valve head 34 being securelyclamped between the upper and lower mandrels 10, 13. To prevent leakageof fluid between the valve seat 12 and the valve head 34, the latter maybe provided with a marginal or circumferential groove 50 in its valveseating face 51, in which is positioned a seal ring 52, of rubber orrubber-like material, adapted to bear against the valve seat 12.

Assuming that the valve is to be reopened, it is merely necessary toelevate the tubular string B, which will carry theupper mandrel 10 andhousing 11 upwardly with it relative to the lower mandrel 13, or againto the position disclosed in Fig. 3, the upper mandrel, however, stilloccupying the rotary position disclosed in Fig. l. The valve head 34 maystill be in sealing engagement with the valve seat 12. The tubularstring B and upper mandrel 10 are then rotated inthe proper direction tocause the lower portion 10a of the Lipper mandrel to engage the valvehead 34 and cam it completely to one side and back into the annularspace 33 within the housing memt ber 11, the parts then occupying thepositions disclosed in Fig. 3. At this time, the lower end of thedepending valve head 34 is disposed above the upper end of the lowermandrel 13, whereupon the tubular string B, upper mandrel 10 and housing11 can be lowered once again relative to the lower mandrel, theperiphery of the lower mandrel 13 then sliding over the face 51 of thevalve head and its end14 engaging the end or valve seat 12 on the uppermandrel. Such engagement will cause the mandrels 10, 13 to rotaterelative to each other, because of the inclination ofthe confrontingends 12, 14 of the upper and lower mandrel, or, if desired, the uppermandrel can be rotated with respect to the housing 11 back to theposition shown in Fig. 1, which will then allow the mandrel 10 andhousing 11 to be lowered to the fullest extent determined by engagementof the lower mandrel ange 28 with the lower housing flange 27, in whichthe lower mandrel 13 completely covers the valve head 34, and theconfronting inclined edges 12, 14 of the mandrel are closely adjacentone another, all as disclosed in Fig. 1.

The lower mandrel 13 cannot shift rotationally with respect to thehousing 11 and the valve head 34. However, the upper mandrel 10 can turnto a limited extent with respect to the housing 11 to secure the cammingaction of the valve head 34 back completely into the annular space 33 inthe housing. The extent of rotation of the upper mandrel 10 with respectto the housing 11 is determined by engagement of the transverse housingpin 23 with the ends 24, 25 of the recess 22 in the mandrel flange 16.In the specific design disclosed in the drawings, rotation of the uppermandrel 10 to the right will place it in the position shown in Figs. 3and 4, in which the valve head 34 is cammed completely out of the pathyof travel of the lower mandrel 13, and is coniined within the annularspace 33. Such position of the upper mandrel 10 is delinitely determinedby engagement of the end 24 of the ange recess with the transverse pin23. On the other hand, rotation of the upper mandrel 10 to the left islimited by engagement of the other end 25 of the recess with thetransverse pin 23, which will insure the location of the upper mandrel10 with respect to the housing 11 in the position shown in Fig. l, inwhich the upper and lower mandrels10, 13 are closely adjacent oneanother, or in which position the valve head 34 can move upwardly intoengagement with the valve seat 12 to close the passage 15 through themandrels (Fig. 2).

In order to secure a large diameter passage through the mandrels 10, 13,as compared to the outside diameter of the housing 11, the valve head 34is curved to lit closely around the peripheral portions of the mandrels10, 13 when disposed in a pendant position within the annular housingspace 33, as shown most clearly in Fig. 7. In view of this curved formof the Valve head 34, the valve seat 12 at the lower end iof the uppermandrel 10, and the upper end 14 of the lower mandrel 13, must be curvedto conform therewith, rather than such ends lying in straight diagonalplanes. The seal ring 52 and its groove 50, of course, will also conformin curvature to the marginal portion of the valve seat engaging face 51of the valve head.

If the valve head 34 were formed as a at disk, it is evident that itcould only be disposed completely to one side of the mandrels 10, 13,when the valve is in a completely open position, if the housing 11 weremade sub stantially greater in diameter than indicated on the drawings,to provide a sufficient chordal space across the annular space 33 in thehousing. In the present instance, the curving of the Valve head 34allows a smaller radial width of annular space 33 to be used, which canbe provided by a much smaller diameter housing 11 than would be requiredby the use of a flatvalve head.

In addition to enabling the passage diameter through the apparatus to bemade relatively great in proportion to the outside diameter of thehousing, the curving of the valve head 34 (so that it in effectconstitutes a portion of a cylinder) greatly increases the strength ofthe valve head 34 and permits it to resist much greater pressures whenin its closed position clamped between the valve seat 12 and the upperend 14 of the lower mandrel 13. As a result, it is even possible to makethe valve head somewhat thinner than would be required if it were a llatdisk, which contributes to the production of a valve apparatus with amuch larger diameter through the mandrel passage` 15 as compared to theover-all diameter of the equipment, than could be provided in the eventa at disk were used.

In the use of the apparatus A, it is secured to the lower end of thetubular string B, with its lower end attached to the lower tool C, suchas a well packer, and is run in the well bore with the parts all in therelative positions shown in Fig. l. The valve head 34 is fully protectedfrom the action of fluent materials passing through the mandrel passage15, which is in a fully open condition. At any time that it is desirousto close the valve, it is merely necessary to elevate the tubular stringB, which will raise the upper mandrel 10 and housing 11, the lowermandrel 13 being prevented from moving upwardly by the lower tool C.Upward movement of the upper mandrel 10 and housing 11 will occur untilthe valve head 34 is disposed above the upper end 14 of the lowermandrel 13, the spring arm 41 then projecting the valve head 34 inwardlyuntil it extends partly across the lower mandrel 13. The apparatus isthen lowered, the lower mandrel 13 swinging the head 34 upwardly untilit engages the valve seat 12 and is backed up fully by the lower mandrel13 itself (Fig. 2). Fluid-is now prevented from passing in bothlongitudinal directions through the upper and the lower mandrels 10, 13.

When it is desired to reopen the valve, it is merely necessary toelevate the tubular string B, to raise the upper mandrel 10 and housing11 with respect to the lower mandrel 13, the lower mandrel then beingdisposed at a substantial distance below the Valve head 34. rI'he valvehead may drop away from the valve seat 12, or it may be heldthereagainst by pressure below the apparatus. In any event, when thehousing 11 has been shifted 4upwardly to its fullest extent with respectto the lower mandrel 13, the upper mandrel 10 need merely be rotated tothe right and to the extent determined by engagement of the end 24 ofthe recess 22 with the limit pin 23. During such turning action, thelower portion 10a of the mandrel will engage the face 51 of the valvehead and cam it in a lateral outward direction, swinging it downwardlyand outwardly about its pivot 35 until the valve head 34 again occupiesa position completely within the annular space 33.

The tubular string B, upper mandrel 10 and housing 1l may again berelowered, the valve head 34 merely sliding lover the periphery of thelower mandrel 13, which then holds it in its outward position. Thetubular string B and upper mandrel 10 are then turned to the left, tothe extent limited by engagement of the other end 25 of the recess 22with the limit pin 23, which will rotate the upper mandrel 10 out of theengagement with the valve head 34, and then permit the upper mandrel 10and the housing 11 to be lowered to the fullest extent, determined byengagement of the lower housing flange 27 with the lower mandrel ange28, in which the tapered curved ends 12, 14 of the upper and lowermandrels will be closely adjacent one another.

When it is desired to pump uent materials through the apparatus thevalve parts are placed in the position shown in Fig. l, in which thevalve head 34 is fully protected. Such iluent materials, which mayinclude sand or other abrasive particles used in performing a hydraulicfracturing operation in a well bore, may be pumped through the tubularstring B and through the valve apparatus A, continuing on down to thelower tool C for passage into the formation surrounding the well bore.The fluent materials cannot harm the valve head 34, since it is fullyprotected by the lower mandrel 13. If at any time it is desired to closethe valve, the parts need merely be manipulated in the manner describedabove, and then placed in the relative positions shown in Fig. 2.

Assuming that the apparatus is to be withdrawn from the well bore,elevation of the tubular string B will elevate the upper mandrel 10 andhousing 11 with respect to the lower mandrel 13. When this occurs thespring arm 4l can project the valve head 34 in an inward direction. Thevalve head 34 may remain in open position or it may be caused by fluidpressure from below to swing upwardly into sealing engagement againstthe upper mandrel valve seat 12. The valve apparatus may be raised inthe well bore with the parts in this closed position, which may bedesirable, inasmuch as lluid, such as high pressure gases and the like,would then be prevented from flowing up through the tubular string B. Iffor any reason it is desired to prevent the valve head 13 from engagingits seat during upward movement of the apparatus in the well bore, thenthe tubular string B and upper mandrel l need merely be rotated withrespect to the housing lll, causing the lower portion lila of the uppermandrel to cam the vaive head 3ft completely out of the way and hold itin the annual housing spaced In this position, which is shown in Fig. 3,the apparatus can be elevated in the well bore.

It is, accordingly, evident that a subsurface well bore valve apparatushas been provided which enables a very large diameter and unobstructedpassage to be provided, as compared to the over-all diameter of theapparatus. The valve head 34 may be positively cammed out of the way toan ineffective and protected position, whenever desired, by the uppermandrel l0 itself. The mere fact that the valve seat 12 is substantiallyinclined with respect to the axis of the apparatus causes the lowerportion 16a of the upper mandrel to function as a cam actuator. hecurved valve member 3d enables the overall dimensions of the apparatusto be kept relatively small, while increasing the strength of the valvehead and insuring against its failure upon being subjected tosubstantial pressure.

The inventor claims:

l. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: tubular means having a valve seat disposed in aposition inclined to the axis of the tubular means, wherein the fullwidth of one portion of said seat is axially spaced substantially fromthe full width of a diametrically opposite portion of said seat; a valvehead movable laterally of the axis of said tubular means into and out ofengagement with said seat; and means mounting said tubular means forrotation relative to said valve head, to cause said tubular means, whenrotated, selectively to engage and shift said valve head from said seator to permit said valve head to engage said seat.

2. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an inner tubular member; an outer tubularmember receiving said inner member and rotatable with respect thereto;one of said members having a valve seat disposed in a position inclinedto the axis of said members, wherein the full width of one portion ofsaid seat is axially spaced substantially from the full width of adiametrically opposite portion of said seat; a valve head on the otherof said members movable laterally of the axis of said members into andout of engagement with said seat; relative rotation between said memberscausing the inclined portion of said one member at said seat to cam saidvalve head laterally out of engagement with said seat.

3. In valve apparatus to be incorporated in a tubular string to bedisposed ina well bore: an inner tubular member; an outer tubular memberreceiving said inner member and rotatable with respect thereto; one ofsaid members having a valve seat disposed in a position inclined to theaxis of said members, wherein the full width of one portion of said seatis axially spaced substantially from the full width of a diametricallyopposite portion of said seat; a valve head on the other of said membersmovable laterally of the axis of said members into and out of engagementwith said seat; relative rotation between said members causing theinclined portion of said one member at said seat to cam said valve headlaterally out of engagement with said seat; said members beingrelatively rotatable to an extent at which the periphery of said onemember engages and holds said head completely out of the path of lluidllow through said one member.

4r In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an inner tubular member; an outer tubularmember receiving said inner member and rotatable with respect thereto;one of said members having a valve seat inclined to the axis of saidmembers; a valve head pivotally mounted on the other ef said members andswingable laterally into and out of engagement with said inclined seat;relative rotation between said members causing the inclined portion ofsaid one member at said seat to cam said valve head out of engagementwith said seat; said members being relatively rotatable to an extent atwhich the periphery of said one member engages and holds said headcompletely out of the path of iluid tlow through said one member.

5. in valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; an inner tubularmember rotatably mounted within said outer member and having a valveseat inclined to the axis of said members; a valve pivotally mounted onsaid outer member and swingable into and out of engagement with saidseat; relative rotation between said members causing the inclinedportion of said inner member at said seat to cam said valve head out ofengagement with said seat; said members being relatively rotatable tothe extent at which the periphery of said inner member engages and holdssaid head completely out of the path of tluid tlow through said innermember. 6. In valve apparatus to be incorporated in a tubular string tobe disposed to a well bore: tubular means having a valve seat disposedin a position inclined to the axis of the tubular means, wherein thefull width of one portion of said seat is axially spaced substantiallyfrom the full width of a diametrically opposite portion of said seat; avalve head movable laterally of the axis of said tubular means into andont of engagement with said seat; means mounting said tubular means forrotation relative to said valve head,l to cause said tubular means, whenrotated, selectively to engage and shift said valve head from said seator to permit said valve head to engage said seat; and means movablelongitudinally with respect to said tubular means into and out ofengagement with said head to hold said head against said seat. 7. Invalve apparatus to be incorporated in a tubular string to be disposed ina well bore: tubular means having a valve seat disposed in a postioninclined to the axis of the tubular means, wherein the full width of oneportion of said seat is axially spaced substantially from the full widthof a diametrically opposite portion of said seat; a valve head movablelaterally of the axis of said tubular means into and out of engagementwith said seat; means mounting said tubular means for rotation relativeto said valve head to cause said tubular means, when rotated,selectively to engage and shift said valve head from said seat or topermit said valve head to engage said seat; and means movablelongitudinally with respect to said tubular means to a position acrosssaid valve head to prevent said head from engaging said seat. 8. Invalve apparatus to be incorporated in a tubular string to be disposed ina well bore: tubular means having a valve seat inclined to the axis ofthe tubular means: a valve head movable laterally into and out ofengagement with said seat; means mounting said tubular means forrotation relative to said valve head to cause said tubular means, whenrotated, selectively to engage and shift valve I head from said seat orto permit said valve head to engage said seat; and holding means movablelongitudinally in one direction with respect to said tubular means intoengagement with said head to hold said head against said seat, saidholding means being movable relatively in the opposite direction toallow said tubular means to shift l l l l l l said head from 'said seat,said holding means then being movable relatively in said onelongitudinal direction across said valve head to prevent said head fromengaging said seat. y

9. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; a first inner tubularmember rotatably mounted in said outer member; said inner member havinga valve seat inclined to the axis of said members; a valve head carriedby said outer member and movable laterally into engagement with saidseat; relative rotation 'between said members causing the inclinedportion of said inner member at said seat to cam said valve head out ofengagement with said seat; and a second inner tubular membertelescopically disposed in said outer member and movable relativelytoward and away from said rst inner member to engage and hold said valvehead against said seat or to permit said valve head to move away fromsaid seat.

10. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; a first inner tubularmember rotatably mounted in said outer member; said inner member havinga valve seat inclined to the axis of said members; a valve head carriedby said outer member and movable laterally into engagement with saidseat; relative rotation between said members causing the inclinedportions of said inner member at said seat to cam said valve head out ofengagement with said seat; a second inner mem-ber adapted to engage andhold said valve head against said seat; said second member beingrelatively movable away from said first member to permit said valve headto move away from p said seat, whereupon said second member isrelatively movable toward said first member and across said head to holdsaid head out of engagement with said seat,

11. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; a first inner tubularmember rotatably mounted in said outer member; said inner member havinga valve seat inclined to the axis of said members; a valve headpivotally carried by said outer member and swingable into engagementwith said seat; relative rotation between said members causing theinclined portion of' said inner member at said seat to cam said valvehead out of engagement with said seat; a second inner tubular membertelescopically disposed in `said outer member and movable relativelytoward and away from said first inner member to engage and hold saidvalve head against said seat or to permit said valve head to move awayfrom said seat; said first member and outer member being relativelyrotatable to a position at which the periphery of said rst inner mem'berengages and holds said head completely out of the path of fiuidflow'through said first inner member.

12. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; a rst inner tubularmember rotatably mounted in said outer member; said inner member havinga valve seat inclined to the axis of said members; a valve headpivotally carried by said outer member and swingable into engagementwith said seat; relative rotation between said members causing theinclined portion of said inner member at said seat to cam said valvehead out of engagement with said seat; a second inner tubular membertelescopically disposed in said outer member and movable relativelytoward and away from said first inner member to engage and hold saidvalve head against said seat or to permit said valve head to move awayfrom said seat; said first member and outer member being relativelyrotatable to a position at which the periphery of said first innermember engages and holds said head completely out of the path of fluidow through said first inner member; said valve head being curved toconform generally to the periphery of said iirst inner member.

13. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; an inner tubularmember rotatably mounted within said outer member and having a valveseat inclined to the axis of said members; a valve pivotally mounted onsaid outer member and swingable into and out of engagement with saidseat; relative rotation between said members causing the inclinedportion of said inner member at said seat to cam said valve head out ofengagement with said seat; said members being relatively rotatable tothe extent at which'the periphery of said inner member engages and holdssaid head completely out of the path of fluid flow through said innermember; said Valve head being curved to conform to the periphery of saidinner member.

14. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; a first inner tubularmember rotatably mounted in said outer member; said in ner member havinga valve seat inclined to the axis of said members; a valve headpivotally `carried by said outer member and swingable into engagementwith said seat; relative rotation between said members causing theinclined portion of said inner member at said seat to cam said valvehead out of engagement with said seat; a second inner tubular membertelescopically disposed in said outer member and movable relativelytoward said first inner member to engage and hold said valve headagainst said seat; said first member and outer member being relativelyrotatable to a position at which the periphery of said tirst innermember engages and holds said head completely out of the path of iiuidflow through said irst inner member; said second member being relativelymovable away from said rst member to permit said valve head to be movedaway from said seat by said first member, whereupon said second memberis relatively movable toward said first member to dispose the peripheryof said second member across said head to hold said head out ofengagement with said seat.

15. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; a rst inner tubularmember rotatably mounted in said outer member; said inner member havinga valve seat inclined to the axis of said members; a valve headpivotally carried by said outer member and swingable into engagementwith said seat; relative rotation between said members causing theinclined portion of said inner member at said seat to cam said valvehead out of engagement with said seat; a second inner tubular membertelescopically disposed in said outer member and movable relativelytoward said first inner member to engage and hold said valve headagainst said seat; said first member and outer member being relativelyrotatable to a position at which the periphery of said first innermember engages and holds said head completely out of' the path of fluidflow through said first inner member; said second member beingrelatively movable away from said first member to permit said valve headto be moved away from said seat by said first member, whereupon saidsecond member is movable relatively toward said first member to disposethe periphery of said second member across said head to hold said headout of engagement with said seat; said valve head being curved toconform generally to the curvature of the peripheries of said first andsecond member.

16. In valve apparatus to be incorporated in a tubular string tobedisposed in a well bore: an outer tubular member; a first innertubular member rotatably mounted in said outer member; said inner memberhaving a valve seat inclined to the axis of said members; a valve headpivotally carried by said outer member and swingable into engagementwith said seat; relative rotation between said members causing theinclined portion of said inner member at said seat to cam said valvehead out of engagement with said seat; a second inner tubular membertelescopically disposed within and slidably splined to said outer memberand movable relatively toward said first inner member to engage and holdsaid valve head against said seat; said first member and outer memberbeing relatively rotatable to a position at which the periphery of saidfirst inner member engages and holds said head completely out of thepath of fluid flow through said first inner member; said second memberbeing relatively movable away from said first member to permit saidvalve head to be moved away from said seat by said first member,whereupon said second member is movable relatively toward said firstmember to dispose the periphery of said second member across said headto hold said head out of engagement with said seat; said valve headbeing curved to conform generally to the curvature of the peripheries ofsaid first and second members; said second member having an inclined endconformable to and disposable adjacent the inclined seat on said firstinner tubular member when said second member is disposed across saidhead.

17. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; a first inner tubularmember rotatably mounted in said outer member; said inner member havinga valve seat inclined to the axis of said members; a valve headpivotally carried by said outer member and swingable into engagementwith said seat; relative rotation between said members causing theinclined portion of said inner member at said seat to cam said valvehead out of engagement with said seat; a second inner tubular membertelescopically disposed in said outer member and movable relativelytoward and away from said first inner member to engage and hold saidvalve head against said seat or to permit said valve head to move awayfrom said seat; said first member and outer member being relativelyrotatable to a position at which the periphery of said first innermember engages and holds said head completely out of the path of fluidflow through said first inner member; and coengageable stop means onsaid first inner member and outer member for positively limitingrelative rotation between said first member and outer member to aposition at which said valve head can engage said seat or to a positionat which the periphery of said first inner member engages said valvehead to hold said valve head from said seat.

18. In valve apparatus to be incorporated in a tubular string to bedisposed in a well bore: an outer tubular member; a first inner tubularmember rotatably mounted in said outer member; said inner member havinga valve seat inclined to the axis of said members; a valve headpivotally carried by said outer member and swingable into engagementwith said seat; relative rotation between said members causing theinclined portion of said inner member at said seat to cam said valvehead out of engagement with said seat; a second inner tubular membertelescopically disposed within and slidably splined to said outer memberand movable relatively toward said first inner member to engage and holdsaid valve head against said seat; said first member and outer memberbeing relatively rotatable to a position at which the periphery of saidfirst inner member engages and holds said head completely out of thepath of uid flow through said first inner member; said second memberbeing relatively movable away from said first member to permit saidvalve head to be moved away from said seat by said first member,whereupon said second member is movable relatively toward said firstmember to dispose the periphery of said second member across said headto hold said head out of engagement with said seat; said valve headbeing curved to conform generally to the curvature o'f the peripheriesof said first and second members; said second member having an inclinedend conformable to and disposable adjacent the inclined seat on saidfirst inner tubular member when said second member is disposed acrosssaid head; and coengageable stop means on said first member and outermember for positively limiting relative rotation between said firstmember and outer member to a position in which said valve head can moveinto engagement with said seat or to a position at which the peripheryof said first member holds said valve head completely out of the path offluid flow through said inner members,

References Cited in the file of this patent UNITED STATES PATENTS2,162,578 Hacker June 13, 1939 2,447,842 Cameron Aug. 24, 1948 2,461,617Waters Feb. 15, 1949

